1. Field of the Invention
The present invention relates to an improvement in a camera which is capable of reading information from a magnetic memory of a film or writing information to it.
2. Related Background Art
U.S. Pat. No. 4977419 and other patents disclose cameras each using a magnetic head to read or write information from or to the magnetic memory of a film.
Such a magnetic memory of a predetermined track width is disposed along the film edge in the direction in which the film is fed. If the film is moved up and down or tilted while information is read from or written to the narrow magnetic memory by the magnetic head, the relative positions of the magnetic head and the magnetic memory are changed, and the information cannot be read or written accurately. For this reason, the applicant of this invention applied for Japanese Patent Application Nos. such as 1-34408 and 2-72111. Each of the applications disclose a camera in which a magnetic head secured to a pressure plate moves as the film moves. The relative positions of the magnetic head and the magnetic memory remain constant. It is thus always possible to accurately read or write information.
The above conventional art, however, has the following problem. Cameras have become smaller in recent years, and magnetic heads and film-feeding motors have been arranged closer to each other. Because of an extremely weak signal output from the magnetic head, noise from the film-feeding motor and other components is carried on the output signal before an amplifying circuit amplifies the output signal. Information is thus read or written incorrectly.